Hardening by annealing in the medium-entropy alloy CrCoNi after equal-channel angular pressing

Rymer LM, Höppel HW, Ortner P, Pfeffer N, Stark A, Winter L, Lampke T (2026)

Publication Type: Journal article

Publication year: 2026

Journal

Materials Today Communications Elsevier

Book Volume: 51

Article Number: 114751

DOI: 10.1016/j.mtcomm.2026.114751

Abstract

After equal-channel angular pressing (ECAP) and a subsequent heat treatment at 600 °C for 1 h, the MEA CrCoNi is characterized by a yield strength of about 1.4 GPa but a drastically low uniform elongation of 1.2 %. High-energy X-ray diffraction analysis, transmission electron microscopy, and high-resolution high-angle annular dark-field scanning transmission electron microscopy investigations were performed, but the cause of the annealing-induced hardening could not be conclusively determined, although differential scanning calorimetry measurements reveal an exothermic peak and thus microstructural changes in the temperature range between 450 °C and 650 °C. Despite the complex nature of the MEA CrCoNi, the dominant deformation mechanisms after ECAP processing and a subsequent heat treatment during straining appear to be similar to those of conventional alloys. It is assumed that the rearrangement of dislocations in low-energy configurations and, to some extent, grain and twin boundary relaxation lead to the anneal-induced hardening effect at 600 °C. Grain boundary dislocations are hindered from bowing out or activating new dislocation sources, resulting in the strong increase in yield and ultimate tensile strength.

Authors with CRIS profile

Heinz Werner Höppel Lehrstuhl für Werkstoffwissenschaften (Allgemeine Werkstoffeigenschaften) Patrick Ortner Lehrstuhl für Werkstoffwissenschaften (Allgemeine Werkstoffeigenschaften) Nina Pfeffer Lehrstuhl für Werkstoffwissenschaften (Allgemeine Werkstoffeigenschaften)

Involved external institutions

Technische Universität Chemnitz DE Germany (DE) Helmholtz-Zentrum Hereon DE Germany (DE)

How to cite

APA:

Rymer, L.M., Höppel, H.W., Ortner, P., Pfeffer, N., Stark, A., Winter, L., & Lampke, T. (2026). Hardening by annealing in the medium-entropy alloy CrCoNi after equal-channel angular pressing. Materials Today Communications, 51. https://doi.org/10.1016/j.mtcomm.2026.114751

MLA:

Rymer, Lisa Marie, et al. "Hardening by annealing in the medium-entropy alloy CrCoNi after equal-channel angular pressing." Materials Today Communications 51 (2026).

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